Class
GtkIMContext
since: 3.0
Description [src]
abstract class Gtk.IMContext : GObject.Object
{
/* No available fields */
}
GtkIMContext
defines the interface for GTK+ input methods. An input method
is used by GTK+ text input widgets like GtkEntry
to map from key events to
Unicode character strings.
The default input method can be set programmatically via the
GtkSettings:gtk-im-module
GtkSettings property. Alternatively, you may set
the GTK_IM_MODULE environment variable as documented in
[Running GTK+ Applications][gtk-running].
The GtkEntry
GtkEntry:im-module
and GtkTextView
GtkTextView:im-module
properties may also be used to set input methods for specific widget
instances. For instance, a certain entry widget might be expected to contain
certain characters which would be easier to input with a certain input method.
An input method may consume multiple key events in sequence and finally output the composed result. This is called preediting, and an input method may provide feedback about this process by displaying the intermediate composition states as preedit text. For instance, the default GTK+ input method implements the input of arbitrary Unicode code points by holding down the Control and Shift keys and then typing āUā followed by the hexadecimal digits of the code point. When releasing the Control and Shift keys, preediting ends and the character is inserted as text. Ctrl+Shift+u20AC for example results in the ⬠sign.
Additional input methods can be made available for use by GTK+ widgets as
loadable modules. An input method module is a small shared library which
implements a subclass of GtkIMContext
or GtkIMContextSimple
and exports
these four functions:
void im_module_init(GTypeModule *module);
This function should register the GType
of the GtkIMContext
subclass which
implements the input method by means of g_type_module_register_type(). Note
that g_type_register_static()
cannot be used as the type needs to be
registered dynamically.
void im_module_exit(void);
Here goes any cleanup code your input method might require on module unload.
void im_module_list(const GtkIMContextInfo ***contexts, int *n_contexts)
{
*contexts = info_list;
*n_contexts = G_N_ELEMENTS (info_list);
}
This function returns the list of input methods provided by the module. The
example implementation above shows a common solution and simply returns a
pointer to statically defined array of GtkIMContextInfo
items for each
provided input method.
GtkIMContext * im_module_create(const gchar *context_id);
This function should return a pointer to a newly created instance of the
GtkIMContext
subclass identified by context_id
. The context ID is the same
as specified in the GtkIMContextInfo
array returned by im_module_list().
After a new loadable input method module has been installed on the system,
the configuration file gtk.immodules
needs to be
regenerated by [gtk-query-immodules-3.0][gtk-query-immodules-3.0],
in order for the new input method to become available to GTK+ applications.
Available since: 3.0
Instance methods
gtk_im_context_delete_surrounding
Asks the widget that the input context is attached to to delete
characters around the cursor position by emitting the
GtkIMContext::delete_surrounding signal. Note that offset
and n_chars
are in characters not in bytes which differs from the usage other
places in GtkIMContext
.
since: 3.0
gtk_im_context_filter_keypress
Allow an input method to internally handle key press and release
events. If this function returns TRUE
, then no further processing
should be done for this key event.
since: 3.0
gtk_im_context_focus_in
Notify the input method that the widget to which this input context corresponds has gained focus. The input method may, for example, change the displayed feedback to reflect this change.
since: 3.0
gtk_im_context_focus_out
Notify the input method that the widget to which this input context corresponds has lost focus. The input method may, for example, change the displayed feedback or reset the contexts state to reflect this change.
since: 3.0
gtk_im_context_get_preedit_string
Retrieve the current preedit string for the input context, and a list of attributes to apply to the string. This string should be displayed inserted at the insertion point.
since: 3.0
gtk_im_context_get_surrounding
Retrieves context around the insertion point. Input methods typically want context in order to constrain input text based on existing text; this is important for languages such as Thai where only some sequences of characters are allowed.
since: 3.0
gtk_im_context_reset
Notify the input method that a change such as a change in cursor position has been made. This will typically cause the input method to clear the preedit state.
since: 3.0
gtk_im_context_set_client_window
Set the client window for the input context; this is the
GdkWindow
in which the input appears. This window is
used in order to correctly position status windows, and may
also be used for purposes internal to the input method.
since: 3.0
gtk_im_context_set_cursor_location
Notify the input method that a change in cursor position has been made. The location is relative to the client window.
since: 3.0
gtk_im_context_set_surrounding
Sets surrounding context around the insertion point and preedit string. This function is expected to be called in response to the GtkIMContext::retrieve_surrounding signal, and will likely have no effect if called at other times.
since: 3.0
gtk_im_context_set_use_preedit
Sets whether the IM context should use the preedit string
to display feedback. If use_preedit
is FALSE (default
is TRUE), then the IM context may use some other method to display
feedback, such as displaying it in a child of the root window.
since: 3.0
Signals
Gtk.IMContext::commit
The ::commit signal is emitted when a complete input sequence has been entered by the user. This can be a single character immediately after a key press or the final result of preediting.
since: 3.0
Gtk.IMContext::delete-surrounding
The ::delete-surrounding signal is emitted when the input method needs to delete all or part of the context surrounding the cursor.
since: 3.0
Gtk.IMContext::preedit-changed
The ::preedit-changed signal is emitted whenever the preedit sequence
currently being entered has changed. It is also emitted at the end of
a preedit sequence, in which case
gtk_im_context_get_preedit_string()
returns the empty string.
since: 3.0
Gtk.IMContext::preedit-end
The ::preedit-end signal is emitted when a preediting sequence has been completed or canceled.
since: 3.0
Gtk.IMContext::preedit-start
The ::preedit-start signal is emitted when a new preediting sequence starts.
since: 3.0
Gtk.IMContext::retrieve-surrounding
The ::retrieve-surrounding signal is emitted when the input method
requires the context surrounding the cursor. The callback should set
the input method surrounding context by calling the
gtk_im_context_set_surrounding()
method.
since: 3.0
Signals inherited from GObject (1)
GObject::notify
The notify signal is emitted on an object when one of its properties has its value set through g_object_set_property(), g_object_set(), et al.
since: 2.0
Class structure
struct GtkIMContextClass {
void (* preedit_start) (
GtkIMContext* context
);
void (* preedit_end) (
GtkIMContext* context
);
void (* preedit_changed) (
GtkIMContext* context
);
void (* commit) (
GtkIMContext* context,
const gchar* str
);
gboolean (* retrieve_surrounding) (
GtkIMContext* context
);
gboolean (* delete_surrounding) (
GtkIMContext* context,
gint offset,
gint n_chars
);
void (* set_client_window) (
GtkIMContext* context,
GdkWindow* window
);
void (* get_preedit_string) (
GtkIMContext* context,
gchar** str,
PangoAttrList** attrs,
gint* cursor_pos
);
gboolean (* filter_keypress) (
GtkIMContext* context,
GdkEventKey* event
);
void (* focus_in) (
GtkIMContext* context
);
void (* focus_out) (
GtkIMContext* context
);
void (* reset) (
GtkIMContext* context
);
void (* set_cursor_location) (
GtkIMContext* context,
GdkRectangle* area
);
void (* set_use_preedit) (
GtkIMContext* context,
gboolean use_preedit
);
void (* set_surrounding) (
GtkIMContext* context,
const gchar* text,
gint len,
gint cursor_index
);
gboolean (* get_surrounding) (
GtkIMContext* context,
gchar** text,
gint* cursor_index
);
void (* _gtk_reserved1) (
void
);
void (* _gtk_reserved2) (
void
);
void (* _gtk_reserved3) (
void
);
void (* _gtk_reserved4) (
void
);
void (* _gtk_reserved5) (
void
);
void (* _gtk_reserved6) (
void
);
}
Class members
preedit_start: void (* preedit_start) ( GtkIMContext* context )
- No description available.
preedit_end: void (* preedit_end) ( GtkIMContext* context )
- No description available.
preedit_changed: void (* preedit_changed) ( GtkIMContext* context )
- No description available.
commit: void (* commit) ( GtkIMContext* context, const gchar* str )
- No description available.
retrieve_surrounding: gboolean (* retrieve_surrounding) ( GtkIMContext* context )
- No description available.
delete_surrounding: gboolean (* delete_surrounding) ( GtkIMContext* context, gint offset, gint n_chars )
- No description available.
set_client_window: void (* set_client_window) ( GtkIMContext* context, GdkWindow* window )
- No description available.
get_preedit_string: void (* get_preedit_string) ( GtkIMContext* context, gchar** str, PangoAttrList** attrs, gint* cursor_pos )
- No description available.
filter_keypress: gboolean (* filter_keypress) ( GtkIMContext* context, GdkEventKey* event )
- No description available.
focus_in: void (* focus_in) ( GtkIMContext* context )
- No description available.
focus_out: void (* focus_out) ( GtkIMContext* context )
- No description available.
reset: void (* reset) ( GtkIMContext* context )
- No description available.
set_cursor_location: void (* set_cursor_location) ( GtkIMContext* context, GdkRectangle* area )
- No description available.
set_use_preedit: void (* set_use_preedit) ( GtkIMContext* context, gboolean use_preedit )
- No description available.
set_surrounding: void (* set_surrounding) ( GtkIMContext* context, const gchar* text, gint len, gint cursor_index )
- No description available.
get_surrounding: gboolean (* get_surrounding) ( GtkIMContext* context, gchar** text, gint* cursor_index )
- No description available.
_gtk_reserved1: void (* _gtk_reserved1) ( void )
- No description available.
_gtk_reserved2: void (* _gtk_reserved2) ( void )
- No description available.
_gtk_reserved3: void (* _gtk_reserved3) ( void )
- No description available.
_gtk_reserved4: void (* _gtk_reserved4) ( void )
- No description available.
_gtk_reserved5: void (* _gtk_reserved5) ( void )
- No description available.
_gtk_reserved6: void (* _gtk_reserved6) ( void )
- No description available.
Virtual methods
Gtk.IMContextClass.delete_surrounding
Asks the widget that the input context is attached to to delete
characters around the cursor position by emitting the
GtkIMContext::delete_surrounding signal. Note that offset
and n_chars
are in characters not in bytes which differs from the usage other
places in GtkIMContext
.
since: 3.0
Gtk.IMContextClass.filter_keypress
Allow an input method to internally handle key press and release
events. If this function returns TRUE
, then no further processing
should be done for this key event.
since: 3.0
Gtk.IMContextClass.focus_in
Notify the input method that the widget to which this input context corresponds has gained focus. The input method may, for example, change the displayed feedback to reflect this change.
since: 3.0
Gtk.IMContextClass.focus_out
Notify the input method that the widget to which this input context corresponds has lost focus. The input method may, for example, change the displayed feedback or reset the contexts state to reflect this change.
since: 3.0
Gtk.IMContextClass.get_preedit_string
Retrieve the current preedit string for the input context, and a list of attributes to apply to the string. This string should be displayed inserted at the insertion point.
since: 3.0
Gtk.IMContextClass.get_surrounding
Retrieves context around the insertion point. Input methods typically want context in order to constrain input text based on existing text; this is important for languages such as Thai where only some sequences of characters are allowed.
since: 3.0
Gtk.IMContextClass.reset
Notify the input method that a change such as a change in cursor position has been made. This will typically cause the input method to clear the preedit state.
since: 3.0
Gtk.IMContextClass.set_client_window
Set the client window for the input context; this is the
GdkWindow
in which the input appears. This window is
used in order to correctly position status windows, and may
also be used for purposes internal to the input method.
since: 3.0
Gtk.IMContextClass.set_cursor_location
Notify the input method that a change in cursor position has been made. The location is relative to the client window.
since: 3.0
Gtk.IMContextClass.set_surrounding
Sets surrounding context around the insertion point and preedit string. This function is expected to be called in response to the GtkIMContext::retrieve_surrounding signal, and will likely have no effect if called at other times.
since: 3.0
Gtk.IMContextClass.set_use_preedit
Sets whether the IM context should use the preedit string
to display feedback. If use_preedit
is FALSE (default
is TRUE), then the IM context may use some other method to display
feedback, such as displaying it in a child of the root window.
since: 3.0